Touchstonesby Mario Vargas Llosa, edited and translated by John King (Faber, £25)

In these selected "Essays on Literature, Art and Politics" the novelist writes on a rich range of subjects that include Woolf, Hemingway, Grass, Gauguin, Pinochet and postwar Iraq. As a practitioner-critic, he is fascinated by the technical ways in which, say, Cervantes solved certain "problems" of narrative, but can also be moralistic about the uses of literature. He is in awe, for example, of the "almost demonic complexity" of Nabokov's craftsmanship in Lolita, but it is a backhanded compliment, because Vargas Llosa is sighing with relief that, for once, the demonic complexity does not overshadow the story. (Nabokov and Borges, he thinks, wanted to "remain protected, removed from the world through their prodigious inventive games that diluted reality into a labyrinth of words and phosphorescent images". Well, maybe, a bit; but then, what of it?) On the other hand, there is an excellent essay on Conrad's Heart of Darkness, which magically reminds us of that story's strangeness; and a charming account of how the author cured his fear of flying by choosing the right novels to read (for fellow sufferers, he recommends Melville's Bartleby and Benito Cereno). The best piece is probably the 53-page "Iraq Diary", an account of 12 days spent in Iraq in June 2003, in which his gifts of evocation, sympathetic character-sketching, comic anecdotalism and subtle technical games with point of view (there is a particularly fine passage written in what might be called the conditional second person) make for a vivid and complex account of people's lives and hopes.

The story of this amazing and beautifully written little book is one of humans very gradually, and only through gritted teeth, admitting that other animals, down to the apparently humblest insects, are more intelligent than was ever suspected. Here are spiders that make silk nets to throw over their prey; male birds that build purely decorative "sculptures" to attract mates; the extraordinarily sophisticated topographical language of honey-bee dances; the dumbfounding hydraulic planning of beavers; tailorbirds that stitch together leaves with spider-silk; and even the idea, bruited during the second world war, of training birds as kamikaze bombers. The authors recount the ingenious experiments that have overturned standard notions of simple innate "programs" for such behaviour. Instead, it is made clear that in many cases the little beasts can learn and improvise, and must have "cognitive maps" - of the environment or even their fellows' attitudes. In some cases these are so sophisticated as to threaten our own sense of massive superiority. Instead, it seems that intelligence can be found almost anywhere you care to look.

Feeding People Is Easyby Colin Tudge (Pari Publishing, £9.99)

A charming polemic against "the nonsense churned out by the modern food industry". There is no secret, Tudge says, about what a healthy diet is: "plenty of plants, not much meat, and maximum variety", which is also the basis of the most gastronomically delicious diets, as proven by the accumulated wisdom of millennia of peasant cooking. By a magical serendipity, it is also the correct balance for a farm, in terms of soil and ecology. So why does modern agribusiness function differently? Because it's run to maximise profit and "efficiency" - a concept defined, Tudge laments, only in monetary terms. Yet if we were not wasting crops by breeding so much superfluous livestock in order to fuel the western obesity boom, there would be plenty of food to go around, even for the projected population of the Earth in 2050. Tudge thinks that a large part of the problem is that our rulers are stupid and venal. Most people being nice, however, there is hope - if only we can transform our wishes for "enlightened agriculture" into reality. It whets the appetite, physical and moral.